Dental instrument



A. L. HAMILTON.

DENTAL INSTRUMENT.

APPLICATION FILED NOV. 13. 1915;

l 1 95,465. Patented A11 22,1916.

ARTHUR L. HAMILTON, OF HOUSTON, TEXAS.

DENTAL INSTRUMENT.

Specification of Letters Patent.

Patented Aug. 22, 1916.

Application filed November 13, 1915. Serial No. 61,251.

To all "whom it may concern:

Be it known that I, ARTHUR L. HAMIL- To-N, a citizen of the United States, residing at Houston, in the county of Harris and State of Texas, have invented certain new and useful Improvements in Dental Instruments, of which the following is a specification.

This invention relates to new and useful improvements in a dental instrument.

The object of the invention is to provide a device of the character described designed to be used for removing the enamel around the base of a tooth preparatory to crowning the same and may be also employed for the purpose of removing crowns from teeth.

With the above and other objects in view the invention has particular relation to certain novel features of construction and operation an example of which is given in this specification and illustrated in the accompanying drawings wherein:

Figures 1 and 2 respectively show plan and side views of the complete device. Figs. 3 and 4 show fragmentary plan and side views thereof. Fig. 5 shows an end view thereof. Figs. 6 and 7 show, respectively, forms of support employed when the device is in use. Figs. 8 and 9, respectively, show side elevations of the crown remover viewed from different angles. Figs. 10 and 11 show side views of the enamel remover viewed from opposite sides, and Fig. 12 shows an end view of the remover.

Referring now more particularly to the drawings wherein like numerals of reference designate similar parts in each of the figures the numerals 1 and 2 refer, respectively, to the handles of the instrument which are pivoted together at the point 3 so that when the grip ends are pressed together the opposite ends will be open and said grip ends are normally .held apart by a flat spring, one end of which is secured to the handle 2 and whose free end rests against the inner side of the handle 1. The operative ends of the handles 1 and 2 are enlarged and formed into conical shaped disks 5 and 6, to the former of which the enamel or crown remover 7 and 8 may be detachably secured. These parts 7 and 8 are pins having enlarged heads. The disk 5 has a central orifice through which the pin passes and whose upper end is enlarged forming a socket in which the enlarged head of the pin seats and the handle 1 has a flat spring 9, one end of wlnch is pivoted thereto and whose other end is bent over to engage in the transverse groove 10 in the head of the pin to secure the same in position. The body of the pin passes through an alined central orifice in the disk 6. The free end of the pin 7 has a cutting blade 11 whose edge extends diagonally relative to the axis of the pin and the pin 8 has its free end formed into a hook 12 for a purpose to be hereinafter set forth.

In preparing a tooth to receive what is known as a shell crown, the enamel must be first ground ofi. The exposed portion of the enamel is ground off by the ordinary dental tool now in common use but a portion of the enamel around the base of the tooth is not exposed and consequently is not accessible to the ordinary grinding machine but must be removed by hand instruments. For this purpose the pin 7 is inserted in the implement herein described and when the enamel on the outerside of the tooth is being removed it is turned as shown in Figs. 1 and 2 but when the inner side of the tooth is being operated on then the pin 7 is turned as shown in Figs. 3 and 4. A detachable support 13 is provided for use when the outer side of the tooth is being operated on and another form of support 14: is provided when the inner side of the tooth is being cut away. This support is formed of a U-shaped member whosearms slide in the side grooves 15, 15 of the disk 6 and the dif ferent forms of support have the depending tangs 16, 16 and 17, 17 arranged, respectively, at the opposite ends of the U-shaped member. lVhen in operation these tangs rest upon the teeth adjacent the one being operated upon on each side and the free end of the pin 7 passes down between the base of the tooth and the gum and as the implement is operated the cutting edge of the blade 11 cuts away the enamel around the base of the tooth without lacerating the flesh.

In case it is desired to remove a crown from a tooth the pin 8 is inserted and the hook 12 thereof engaged under the edge of the crown and the grip ends of the handles 1 and 2 then forced together and this will operate to force the crown from the tooth. By this operation the crown will be regether, a pin detachably secured to the free end of one of said handles and slidable through an orifice in the corresponding end of the other handle and a detachable U-shaped support having depending tangs carried by said last mentioned handle end.

2. A device of the character described including a pair of handles pivoted together,

a pin detachably secured to the free end of '15 one of said handles and 'slidable through the corresponding end of the other handle and a detachable support having depending tangs carried by said last mentioned handle end. 20

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.-

ARTHUR L. HAMILTON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

